Odds of genetic trait inheritance using probability?

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In summary, the Hardy-Weinberg equilibrium would hold between heterozygous (pq) and homozygous (p or q) offspring if p+q=1 and p^2+2pq+q^2=1.
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itlivesthere
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I'd like to find out a way to predict how dominant a particular trait would be over the course of a particular number of generations. There will be only two traits going head to head, each with a particular probability of outcome.

Let's say the probability that Trait A will display as the phenotype of the population's offspring would be 50.1% (501 per 1000 births).
Let's say the probability that Trait B will display as the phenotype of the population's offspring would be 49.9% (499 per 1000 births).
The estimated total fertility rate is 2.36 children per woman.

I understand that many more variables would be needed for accurate figures, but I'm more interested in a general result to begin with.

Over the course of 8,000 generations of offspring and a constant fertility rate of 2.36, which percentage of the population would display the phenotype of Trait A or of Trait B?

(Note: I've tried binary logistic regression and even monohybrid crossing, but I seem to be screwing it up somehow.)
 
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  • #2
itlivesthere said:
I'd like to find out a way to predict how dominant a particular trait would be over the course of a particular number of generations. There will be only two traits going head to head, each with a particular probability of outcome.

Let's say the probability that Trait A will display as the phenotype of the population's offspring would be 50.1% (501 per 1000 births).
Let's say the probability that Trait B will display as the phenotype of the population's offspring would be 49.9% (499 per 1000 births).

It's not clear what kind of genetics you're describing. In classical Mendelian genetics the phenotypes resulting from various combinations of dominant (D) and recessive traits (R) will be:

DD=D, DR=D, RD=D, RR=R. Thus the recessive phenotype will appear in 1/4 of the first generation on average.

Where did you get the distribution you described?

EDIT: If you have codominance with 2 alleles, then the Hardy-Weinberg equilibrium should hold between heterozygous (pq) and homozygous (p or q) offspring: That is p + q = 1 and [itex] p^2 + 2pq + q^2 = 1 [/itex]. Why couldn't you just plug your frequencies into this?
 
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  • #3
SW VandeCarr said:
EDIT: If you have codominance with 2 alleles, then the Hardy-Weinberg equilibrium should hold between heterozygous (pq) and homozygous (p or q) offspring: That is p + q = 1 and [itex] p^2 + 2pq + q^2 = 1 [/itex]. Why couldn't you just plug your frequencies into this?

Correction to the first equation which should be [itex] (p+q)^2 = 1 [/itex].
 

1. What is the probability of inheriting a genetic trait from a parent?

The probability of inheriting a genetic trait from a parent depends on the specific trait and the genetic makeup of the parent. It can range from 0% to 100%, but for most traits, it is around 50%.

2. How is the probability of genetic trait inheritance calculated?

The probability of genetic trait inheritance is calculated using Punnett squares, which take into account the possible combinations of genes from both parents. This allows us to determine the likelihood of a particular trait being inherited.

3. Can the probability of genetic trait inheritance change from generation to generation?

Yes, the probability of genetic trait inheritance can change from generation to generation. This is because of the random nature of genetic recombination during reproduction, which can result in different combinations of genes being passed down to offspring.

4. Are there factors that can influence the probability of genetic trait inheritance?

Yes, there are several factors that can influence the probability of genetic trait inheritance, such as the dominance of certain genes, the presence of multiple genes contributing to a trait, and environmental factors that can affect gene expression.

5. How accurate is the use of probability in predicting genetic trait inheritance?

Using probability to predict genetic trait inheritance is not 100% accurate, as it is based on statistical likelihood rather than definite outcomes. However, it is a useful tool for understanding the inheritance patterns of genetic traits and can provide valuable insights for genetic counseling and research.

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